The invention concerns a method and a service unit for controlling the setting-up of a communication connection by a communication network, in which during the call set-up a service request message for requesting a service is transmitted to a network server if the communication connection that is to be set up fulfils predetermined trigger conditions.
The invention is based on the provision of services within a telephone network by means of the IN (Intelligent Network) architecture. The provision of a special IN service by a network server is described in U.S. Pat. No. 5,345,502.
Terminals are interconnected via a telephone network that has switching centres, which provide the function of service switching points of an IN architecture. Based on a service identification entered in a call request, these switching centres transmit a service request message to a network server that fulfils the function of a service control point in the IN architecture: if the service switching point detects that the service identification assigned to the IN service is entered in the call request, then it transmits the service request message to the network server. The network server then controls the provision of the IN service. To do this it can initiate the rerouting of the communication connection by the telephone network by transmitting control commands, among other things.
Now the object of the invention is to enhance the availability of services.
This object is achieved by a method for controlling the setting-up of communication connections by a communication network as well as a service unit for controlling the setting-up of communication connections by a communication network.
Here the invention is based on the idea that service requests directed to a network server are classified as essential or non-essential. If the network server is no longer operative, the further call set-up is enabled for those connections whose assigned service request is classified as non-essential and the call set-up is terminated for those connections whose assigned service request is classified as essential.
The advantage of the invention is that even in the event of failure of network servers, the setting-up of a number of communication connections by the communication network is still possible and at the same time the infrastructure of the communication network is protected against unauthorised access. Furthermore, this makes it possible to implement services in a more cost-effective manner since it enables at least the duplication of some network servers to be avoided.
Advantageous developments of the invention are revealed in the sub-claims.